error: unused borrow that must be used
  --> $DIR/unused-borrows.rs:6:5
   |
LL |     &42;
   |     ^^^
   |
note: the lint level is defined here
  --> $DIR/unused-borrows.rs:1:9
   |
LL | #![deny(unused_must_use)]
   |         ^^^^^^^^^^^^^^^

error: unused borrow that must be used
  --> $DIR/unused-borrows.rs:9:5
   |
LL |     &mut foo(42);
   |     ^^^^^^^^^^^^

error: unused borrow that must be used
  --> $DIR/unused-borrows.rs:12:5
   |
LL |     &&42;
   |     ^^^^

error: unused borrow that must be used
  --> $DIR/unused-borrows.rs:15:5
   |
LL |     &&mut 42;
   |     ^^^^^^^^

error: unused borrow that must be used
  --> $DIR/unused-borrows.rs:18:5
   |
LL |     &mut &42;
   |     ^^^^^^^^

error: unused borrow that must be used
  --> $DIR/unused-borrows.rs:23:5
   |
LL |     && foo(42);
   |     ^^^^^^^^^^

error: aborting due to 6 previous errors